A Facile and Efficient Method to Fabricate Highly Selective Nanocarbon Catalysts for Oxidative Dehydrogenation

Abstract

Carbon nanotubes (CNTs) were used in oxidative dehydrogenation (ODH) reactions. Quinone groups on the CNT surface were identified as active sites for the dehydrogenation pathway. Liquid-phase oxidation with HNO is one way to generate various oxygen functionalities on the CNT surface but it produces a large amount of acid waste, limiting its industrial application. Here, a facile and efficient oxidative method to prepare highly selective CNT catalysts for ODH of n-butane is reported. Magnesium nitrate salts as precursors were used to produce defect-rich CNTs through solid-phase oxidation. Skeleton defects induced on the CNT surface resulted in the selective formation of quinone groups active for the selective dehydrogenation. The as-prepared catalyst exhibited a considerable selectivity (58 %) to C olefins, which is superior to that of CNTs oxidized with liquid HNO . Through the introduction of MgO nanoparticles on the CNT surface, the desorption of alkenes can be accelerated dramatically, thus enhancing the selectivity. This study provides an attractive way to develop new nanocarbon catalysts.

The Development of Yolk–Shell‐Structured Pd&ZnO@Carbon Submicroreactors with High Selectivity and Stability

“…As to this novel Pd&ZnO@carbon composite, the high phenylacetylene conversion is probably ascribed to the carbon submicroreactor, which can enrich the phenylacetylene accumulation by confinement effect, enhancing the collision frequency and adsorption of phenylacetylene on the Pd nanoparticles surface . Meanwhile, ZnO nanoparticles in situ embedded inside the carbon submicroreactor provide a basic environment which can promote desorption of phenylethylene and prohibit its overhydrogenation . Therefore, the high phenylacetylene conversion and phenylethylene selectivity over Pd&ZnO@carbon catalyst can be attributed to the unique multifunctional reactor benefiting both the adsorption of phenylacetylene and the desorption of phenylethylene during the selective hydrogenation reaction.…”

Nanodiamond‐Core‐Reinforced, Graphene‐Shell‐Immobilized Platinum Nanoparticles as a Highly Active Catalyst for the Low‐Temperature Dehydrogenation of n‐Butane

“…Industrial production of these olefins typically involves either the direct dehydrogenation (DDH) or oxidative dehydrogenation (ODH) of paraffin. ODH is an exothermic process and employs oxidants such as gaseous oxygen and carbon dioxide; however, overoxidation of the hydrocarbons is the main limiting factor of this process . Although satisfactory conversion rates and olefin yields can be achieved by the DDH route, higher reaction temperatures are required and side reactions such as cracking and coking are often inevitable .…”

“…ODH is an exothermic process and employso xidants such as gaseous oxygen and carbon dioxide;h owever,o veroxidation of the hydrocarbonsi s the main limiting factor of this process. [1,5] Although satisfactory conversion rates and olefin yields can be achieved by the DDH route, higherr eactiont emperatures are required and side reactions such as cracking and coking are often inevitable. [1] As industries favor the DDH route for high-throughput olefin production, extensive research devoted to reducing the temperature of the process and to improving the olefin yield through catalystd esign has been performed.…”

Graphitized nanocarbon-supported metal catalysts: synthesis, properties, and applications in heterogeneous catalysis

“…The dehydrogenation of alkane is a fundamental industrial application in the chemical industry for manufacturing polymers, oxygenates, and other intermediates [162][163][164][165][166][167][168]. Liu et al [48] prepared nanocarbon-supported (nanodiamond core and a graphitic shell) Pt NPs (Pt/ ND@G).…”